It’s all downhill from the age of 27

Mental powers peak at 22 and start declining in late twenties

Old age sets in as early as 27, according to Professor Timothy Salthouse of the University of Virginia.

After a seven-year study of 2,000 healthy people aged 18-60,published in the journal Neurobiology of Aging, he found that reasoning, spatial visualisation and speed of thought all begin to decline in our late 20s.

Memory stayed intact until an average age of 37 while performance on tests of vocabulary or general information, increased until the age of 60.

But the average age at which the top performance was achieved was 22. Professor Salthouse told the BBC that his findings suggested 'some aspects of age-related cognitive decline begin in healthy, educated adults when they are in their 20s and 30s'.

Rebecca Wood of the Alzheimer's Research Trust, said: 'Understanding more about how healthy brains decline could help us understand what goes wrong in serious diseases like Alzheimer's.'

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